System of control



C P. TAYLOR.

SYSTEM OF CONTROL.

APPLICATION man FEB. 24, I916.

Patented Dec. 28, 1920.

c. P. TAYLOR.

SYSTEM OF CONTROL.

APPLICATION FILED FEB. 24, 1916.

363,757. Patented Dec. 28, 1920.

2 SHEETS-SHEET 2- 6 fit/Nd WITNESSES: YIINVENTOR 1% 4 [ar/ 7&y/0r

/ ATTORNEY UNITED STATES PATENT QFii lCE.

CAB/L I. TAYLOR, 0F NORE'QLK, VII? ZNIA, ASSIGNQE IG VfEETEI'G-EIOUSEELEC' & MANUFACTURING COIFIEAITY,

SYSTEII OF GONTEGL.

To all whom 2'25 may concern:

Be it known that l, CARL P. TAYLOR, a citizen of the United States, andresident of Norfolk, in the county of Norfolk a id tate of Virginia,have invented a new and useful Improvement in Systems of Control, ofwhich the following is a specification.

My invention relates to systems of control, and especially to theregenerative control of electric railway motors and the like.

One object of my invention is to provide a system of the above-indicatedcharacter which shall be relatively simple and inexpensive inconstruction, which shall be capable of ready adaptation to variousstandard forms of control systems, and which shall provide the usualadvantages or" dynamic braking and regenerative control, such as economyof energy and wear of brakes shoes, etc.

Another object of my invention is to provide a simple and reliable typeof braking control system wherein the momentumdriven machines areconnected in a local circuit under preliminary regenerative conditionsand, when the dynamic voltage or current has increased to apredetermined value, the local circuit is automatically connected toreturn regenerative energy to the supply circuit.

A further object of my invention is to provide a relatively simple andreliable relay means for effecting the abovementioned automaticconnection of the local dynamic raking circuit to the supply circuit,said relay means being; also adapted to automatically reestablish thelocal braking circuit at the end of the regenerative period.

A still further object of my invention is to provide a system ofregenerative control wherein the machine armatures are initiallyconnected in parallel-relation across the sup )ly circuit, with thefield-winding circuit connected in parallel relation to the armaturecircuit, and means associated with the above-mentioned relay means forautomatically effecting the transition of the motor arn'iatures toseries relation when the ma chine speeds have decreased to apredeternined value.

Another object of my invention is to provide a system of the type underconsidera tion wherein a multi-position switching device embodies meansfor connecting the machine or machines to the supply circuit whenoccupying one position that corresponds to acceleration, and for openingthe supplycircuit connection when in a second position that correspondsto regeneration, and means for employin;' the above-mentioned relaymeans for automatically bridging the opening under suitable circuitconditions.

In the accompanying drawings, Figure 1 is a diagrammatic view of asystem of control embodying my invention; 2 and Fly. are simplifieddiagrammatic views that illustrate various main-circuit connectionsdurin the accelerating period, and Fig. i and 5 are correspondingsimplified diagrammatic views that show the maincircuit connections atvarious times during regeneration.

Referring to Fig. 1 of the drawings, the system shown comprises aplurality of suitable supply-circuit conductors respectively markedTrolley ant Ground, although it will be understood that a plurality ofmetallic-circuit conductors may be employed if desired; a plurality ofdynamo-electric machines respectively havinc; armatures i 11 and A2 andfield windings F1 and F2 oi the series type; main controlling device r Cthat is adapted to occupy a plurality of operative positions (a to h,inclusive; a main reversing switch MB for the usual purpose and withwhich is associated auxiliary reversing switch AME, these reversingswitcnes being adapted to occupy the customary forward and reversepositions, re- SPGCtF. ly marked and,

For. and .otev. in addition, a plurality of positions marked Dyn.standing for dynamic, the dynamic positions being respectively locatedbeyond the va d and the reverse positions; a plurality of seitions A511to Alta, inclusive, an accelerating resistor; a second resistor Rh; thatis employed during regeneration only for a purpose to be described; aplurality of suitable motor cut-out swit hes C-1 and C'@2 for thecustomary function of excluding the respective motors from circuitwhenever necessary or desirable; a relay device BB1 that is employed forconnecting the machines to the supply circuit during regeneration, inamanner to be set forth later; anda second relay device RDZ that isemployed for automatically effecting the transition of themomentum-driven armatures from parallel to series relation undersuitable conditions to be described.

The 13 ClQYiCG rcuits. The actuating coil I H esistor sectionregenerative pevlethn of a cirtil resistor 70 r o: c E throu 1's 5%, andh 3W, 2 1l '7 conductor 20, which are bridged auxiliary ede'vice v .1r.- Qlc'llOl of its poslan osc :1 l r Ied Dynf, and conhissing mg; to 7oil 8 is connected iuul of the main armature ill r the :1ctuzuzingcoil 6a) 15 inc; coil 7 that 1 519101 sections Al braking period, as detionziry and movable c011 at third hold ;e t: r i and r yectn'ely, woe;connectee a e the red 5 occumes its posztmn a" conductors 20 bar 5 1s s;r it N of the stationary contact 8 ll 31' 1 Flt l L \lCtOl' coil 8conductor 30 and. 31., which are 1li1 in either of ons of the auxiliaryand conductcrs 33 1c or red of movable vectii'ely cog 0 pairs o:-:'ststiorr e 13 under nors prei'idee Wi 1 a plua em )ers 10 and theposition a by the a t 001i 6 worlnngiu con incti able spring 5, ""or11211111319; an

respect to the unions 'ous that are effected by prmiideu with 21 thirdmovable contact men .91 w l 16 t fggiih as foll her that is c posed ontl e op, osite side Y aver:- 'ng the series coil of the pivotal. pol? r01- e 2 L J 3 to a i rcdoterinined value at the hers l0 and 11 uuu 2 edl at pair of st ionury co the rod 5 1s tuuted 4 coil. 2!, as clescrlhecI tingthe rod 5 xrereupon, the holdiirged in circ iit by reason of theution 5' cont ct ineinli ers 15 contact memher 14: of the rod devicemaintained in its ;ho1.t the renminder of the d QX'Q'J thoughthe coil'7 1. .A 4 A nectmeineel ll. 41

1s dis se' speed of the 1n0 l1 ZlQlllDGS decreases. Howroller 1sreturned 1 the rod The rel;

occupies the position s position the coil 8 is deenergized throughout taccelerating period one & e motors come to rest an (lg con- 55 duringthe cl pe1tio11 ot the reggc l tive neriod c 1 the momentum-nth ectratethe rod te its normal.

that is show] tie drawing.

hm ted and dezw device for 1e action 01"? the spring .9 is sullimaturesare CxfllllC m J O sition 7" by the coil 7 serves to coune 60 urnmturelation, as here fully set The actuating L' .'L relation wth it Will beunahle means for results may he em- 1 '.l G is connected in s ries mamarmature er, bei

desired to effect acceland that the 11111111 reversing switch MRoccupies its position For., the main controller MC may be moved to itsinitial operative position a,

whereupon a circuit is initially established from the trolley, throughconductor 40, control fingers 41 and 42 which are bridged by contactsegment 4-?) of the auxiliary reversing switch AMR, conductors eleand45, control fingers 4:6 and 47 which are bridged by contact segment 48of the main controller in its position a, conductor 6L9, control fingers50 and 51 which are bridged by contact segment 52 of the auxiliaryreversing switch, conductor 53, the four sections A511 to ABA,inclusive, of the accelerating resistor, conductors 54 and 55, blade 56of the cutout switch CO2, conductor 57, control fingers 58 and 59 whichare bridged by contact segment 60 of the main reversing switch,conductor 61, cooperating stationary and movable contact members 12 and10, respectively, of the relay device RD2 in its accelerating positionsa, conductors 62, actuating coil 6 of the relay device R132, conductor25, armature A1, conductor 34, control fingers and 66 which are bridgedby contact segment 67 of the main reversing switch, conductor 68, fieldwinding F1, conductor 69, blade 70 of the cutout switch CO2, conductor 71, control finger 7 2, control fingers 73 and T l which are bridged bycontact segment 75 of the main controller, conductor 7 6, blade 77 ofthe cutout switch CO-l, conductor 78, field winding F 2, conductor 7 9,control fingers S0 and 81 which are bridged by contact se ment 82 of themain reversing switch, conductors 83 and 84:, armature A2, conductors 85and 26, cotiperating stationary and movable contact members 13 and 11,respectively, of the relay device R132 in its position a, conductor 87,control fingers 88 and 89 which are bridged by contact segment 90 of themain reversing switch, conductor 91, blade 92 of the cutout switch CO1,conductor 93, control fingers 9st and 95 which are bridged by contactsegment 96 of the main controller, and conductor 97 to the neg ativeconductor Ground. The main circuits at this time are illustrated in Fig.2.

Upon actuation oi" the main controller MC to its second position b, acircuit is completed from the contact segment &8 thereof, throughcontrol finger 100, conductor 101, the resistor sections Ah2, AR?) andAIM, and thence through the circuit already traced, whereby the sectionARl of the accelerating resistor is excluded from circuit, and apredetermined degree of acceleration of the motors is effected.

Similarly, when the main controller is moved to its position 0, acircuit is completed from the contact segment 1:8, through controlfinger 102 and conductor 103 to a point intermediate the resistorsections AR2 and AR3, thus excluding the section A 2 from the motorcircuit. Nhen the main control er is moved to its position (Z, onecircuit is established from the contact segment 48, through controlfinger 10% and conductor 105 to a point intermediate the resistorsections Allil and Ali l; while a further circuit is simultaneouslyestablished from the contact segment 4&8, through control fingers 106and 107 and conductor 108 to the conductor 55, whereby a directconnection between conductors a5 and 55 is established, and the resistorsections and A114; are excluded from circuit to disnose the motors infull eries relation.

To effect the transition of the motors from ice to parallel relation,which is accomp ished by the well-known shunting type transition, themain controller may be actuated from position (Z toward its initial.parallel position 6. Under such conditions, a circuit is initiallyestablished from the conductor 71, which is associated with thelow-voltage terminal of the field winding F1, through control lingers 72and 109 which are bridged by contact segment 110, and thence throughcontrol fingers 94 and 95 to the negative conductor Ground, inaccordance with the circuit hereinbeiore traced, whereby the motornaving the armature A2 and the field winding 1* 2 is temporarilyshort-circuited.

Substantially simultaneously with the establishment of the circuit justrecited, the contact segment 75 of the main controller is disengagedfrom the control fingers 78 and 7%, thereby interrupting the circuitconnection between th field winding F1 and the meld winding F2, or, inother words, interrupting the circuit between the two motors; and assoon as the main controller reaches its posion c, the control fingers 7land 107 are bridged by a contact segment 111, thus directly connectingthe temporarily shortcircuited motor to the low-voltage terminal oi" theresistor section A114, as illustrated in a simplified manner in 3.

i y actuating the main controller through its remaining positions 7, g,and h, the conrol fingers 102, 10 l and 106 successively engage thecontact segment 48, whereby the resistor sections A112 and ARA arerespectively excluded r" em circuit in a similar manner to that alreadydescribed, and the motors are disposed in full parallel relation.

Assuming now t rat it is desired to effect etardation of thedynamo-electric machines and the as ciat d vehicle, the main reversingswitch hill may be actuated to its posi tion marked Dyn. that is locatedeyond the for vard position, after the main controller has been returnedto its oil position. It will be observed that, by reason of thedisengagement of control finger ll from contact segment as of theauxiliary reversing switch AMR,

the only possible connection between the dynamo-electric machines andthe supply-circuit conductor Trolley, is the circuit from the trolleythrough conductor 115, the stationary and movable contact members 8 and1, respectively, of th relay device RDl as soon as the relay device hasbeen actuated to its upper or closed position, in a manner to bedescribed, and conductor 116, which is directly connected to theconductor By actuating the main controller iilC to its initial positiona, one circuit is estab lishcd from the at present dcenery'izedconductor through conductor 1r, control fingers l2 and 11? which arebridged by the contact segment 48 ot' the auxiliary reversing switchAMP, conductors 118 and 83, control linger 81, contact segment 119,conductor 120, contact segment 121 and control finger 59 of the mainreversing switch Mil, conductor 61, the stationary and movable contactmembers 12 and 10, respectively, of the relay device in its position a,conductors G2, the actuating coil 6, conductor 25, armature A1,conductor Sal, cont ol tin- 65, contact segment 122, conductor 1223,contact segment 12 1 and control linger 89 of the main reversing switch,conductor 91, blade 92 of the cutout switch C(l l, conductor 98, controlfingers 9e and 95 which are bric ged by contact segment 96 of the maincontroller, and conductor 97 to the negative conductor Ground.

A similar circuit is simultaneously established from the conductor 8-3,through conductor Set, armature A2, conductors and 27, the stationaryand movable contact members 13 and 11, respectively, of the relay devicePD2, conductor 87, control finger 88, contact segments 125 and 12% andcontrol finger 89 of the main reversing switch, and thence to thenegative conductor Ground, in accordance with the circuit alreadytraced. Thus, the momentum-driven arm ires are connected in parallelrelation between the lcwerwmtage terminal of the relay device llDl andGround, with the contact members 10, 11 and 11 of the relay deviceoccupying the relative positions shown in l he field-windingcircuit iscompleted at the same time from conductor 15, through control fingers 16l? which are bridged by contact seonient 18 of the main controller,conductor 1-9, control fingers 50 and 126 which are bridged by contactsegment 12= of the auxiliary reversing switch conductor 128, the entireresistor RE, conductors 129 and 103, accelerating resistor sectionsAll?) and 1 PM conouctors and blade 56 of the cutout switch CU2,conductor 57, control finger 58, contact segment 130, conductor 181,contact segment 182 and control finger 6 of the main re- "ersing switchMR, conductor 68, field wind- Fl, conductor 69, blade 70 of the cutoutsegment 12-2 and control linger S9 of the main reversing switch andthence to the negative conduc or round, as herein- 1 1 a, m eelore setiorrn.

The field windings 1 1 and F2 re thus COill1C"tQCl in series relationresistor r it of suitable value ,ble e or sections irlll and across thecircuit of the momentumdriven armaturcs. The resistor sections A111 andare not included in. circuit for the reason that they are not designedto withstand the relatively long operation that is necessary during}; tregenerative period, whereas the resis'or is suitably proportioned forthe intended function and the sections if l and 111 have su'il ieut capaity p hit 1 th 1r intermittently ret as long; necessary.

t will be observed that a local circuit embedying;- the parallelconncctcd a rmatures, and the sold winding together with resistors in seri srelationviith the armatures, is thus estahl shed, whereby the residualmagnetism or the tield winnings will cil'ect the inauguration andgradual building; up oi a dynamic braking current, and the vehicle isinitially retarded by dynamic braking.

The actuating coil 1 of the relay device llilll has one terminalconnected. through conductor 131 an intermediate point 135 of theresistor LI while the other terminal. or the actuatin coil is connecterthrough co iductor 136 t the lower-voltage terminal of; the resistor.The design of parts is such that upon the traversal oi. a predeterminedcurrent through the field-winding circuit, that corresponds to armaturevoltages of a slightly higher value than supply-circuit voltaye, thevoltage drop across the corresponding portion of the resistor RR issufi'icient to cl'lect the actuation of the relay device BB1 to itsupper or closed position, whereby the above-mentioned conductors 115 and116 are connected, and the local circuit just referred to isautomatically connected to the supply circuit. Thus, the momentum-drivenmachines are autmnatically connected to return regenerative energy tothe supply circuit, the currents in the armature and nerd-winding:circuits flowingin,

same re nective directions as during; dynamic bral ons are suitable,that H hen con i when the spof the machines has dcc caced :1 amount, if:the vehicle is J.

traveling; on level track, or when it is desircd to vary the velocity ofdescent if the vehicle 18 traveling on a down grade, the

main controller MC may be actuated as far as its position (Z, wherebythe resistor sec tions A113 and Alla are excluded from circuit in themanner described in connection with the acceleration 01" the motors. Itwill be understood that any suitable amount oi? resistance or number ofsteps for excluding the same from circuit, may be employed lVhen thespeed of the machines has further decreased to a predetermined value,the relay device RDl will drop to its open position, thus temporarildisconnecting the supply circuit and the above-mentioned local circuit,and the main controller MC may then be temporarily returned to itsinitial position a. l he current then traversing the armature A1 and theactuating coil (3 of the relay device BB2 (by reason of their temporaryconnection in the local braking circuit), decreases to a valuesufiiciently low to permit of the actuation of the rod 5 to its position1' by the actuatin coil '2', which is connected across the resistorsections All?) and APA during regenerative operation, as hereinbetoredescribed. The transition of the armatures from parallel to seriesrelation is thus effected in such a manner that a smooth retardation isinsured, since the licld winding current at this time equals its minimumvalue by reason of the fact that the resistor sections A113, AIM and Eliare all in circuit. The relay device BB2 is subsequently maintained inits position r throughout the braking period, inasmuch as the holdingcoil 8 is rendered operative as soon as the rod 5 occupies the position1", as previously set forth.

The circuit connections that effected by the operation of the relaydevice 3B2 are clearly shown in Fig. 4, wherein it will be observedthat, upon the removal of contact memberslO and 11 from the armaturecircuits and the inclusion of the contact men: ber 14 therein, a seriesrelation of the armatures A2 and A1 is eil'ected, illustrated in Fig. 5.The combined armature voltages will thus be greater than thesupply-circuit voltage, a dynamic braking current will be continued inthe local circuit comprising the armatures and the field windings andwhatever resistors are included in circuit, and, upon the traversal of apredetermined current through the field-winding circuit, the relaydevice RDl will again be actuated to its upper or closed position, inthe manner already set forth, to effect further regeneration.

The fieldwinding connections remain the same as during multipleregeneration of the armatures, and the field excitation may be varied atwill by actuating the main controller as far as its position (Z.

hen regenerative operation has been carried as far as possible, that is,when the Voltage of the combinedarmatures A1 and A2 drops below thesupplycircuit voltage,

of four or more motors natures may be initially allel and subsequentlyin A allel or s ries relation, as the machine speeds dec ease to effect,in general, the same type of operation that l have already set forth. Insuch cases, a larger percenta e of the kinetic energy of the momentu-driven vehicle will be returned to t 'cuit, inasmuch as the addiilingswill be adapted to repiac held-circuit resistance that is employed inthe twomotor equipms t hereinbettore described.

will thus be see that l have provided a relatively simp e andinexpensive regenera- 'steni, and the additional aps that I employ maybe readily and ensively associated with various stands or controlsystems. In accordmy system, dynai. ic braking is T cllected inconnection with the iven machines, regeneration to cuit is nextautomatically cl? nay be automatically cm parall l to series relation,if the end of the regenerative 7 i. i-- -\L m n o the same relay meansthat was en1- plo ou to inaugurate regenerative operation operates toreestablish a local dynamic bralti circu' which is maintained until thevehicle stops or the local circuit is opened by the train operator.

The function or" the switch Sil that is connected in ci cuit with theactuating coil '3" ol' the relay device BB2 is as follows: to preventthe above mentioned automatic transition of the motor armatures fromparallel to series relation, the switch SW may be opened, whereby thecoil 7 cannot be energized and the relay device BB2 remains in itsposition a. Thus, automatic change-over from regeneration to dynamicbraking will occur by the opening of the relay device BB1, as soon asthe regenerative voltage of the parallel-connected armatures decreasesbelow the suppiycircuit voltage.

it will be noted that, whereas the main controller MO is actuated to itsfinal position 7L during acceleration, only the first four positions ato (Z, inclusive, are utilized during the regenerative period. Toprevent the train operator from actuating the .ontroller beyond position(Z, the usual and familiar mechanical interlocking means b tween themain control drums and the re- 1 lrui'ns of controller of the K type noy be readily modifi d to prevent movemain cont-roller beyond position imain reversing switch occupie icr oi its positions DynF, as will beunderstood by those slrilled in the art, and no further description ofsuch interlocking is deemed necessary.

1 desire it to he understood that various modifications of the systemherein shown 1 be effect d without departing from the o e of my iivention. For X- a of the illustrated type of c he familiar remotely contrein a plurality of motor t ches governed through i c or a mastercontroller, l. ay he util 3 d pretu'able. liloreover, ins i. 'liaryreversing switch AME, a ole double-throw linite switch may l; ed as anequivalent, although, by i: i the auxiliary reswitch with the nainreversing switch the necessity of manually throwuch a knife switchwhenever the initial change-over from acceleration to regeneration orvice versa is efifected, is obv'ated, and any mechanical interlockingmeans between in reversing switch and such a knife is also desire,

. (ill dispensed with. l that only such limitations shall e l as areindicated in the appended as my invention: a system or" control, thecombina- 'tla supply circuit and a dynamomachine having an armature anda field winding of the series type, of means ror connecting saidarmature and field winding in a local brahin5;- circuit underpreliminary regenerative conditions, and means dependent upon condititnsin said lo a1 circuit for autoi i tically connecting said armature andfield winding in substantial parallel relation across said supplycircuit.

2. 1'1 a system of regenerative control,the upply circuit and acombination with a s lu a ity of dynamo-electric machines sever havingarmatures and field windings, c 21103 for cornectinp; said arinatures inp cl :elation and said field windings in series relation therewith in anindependent local circuit, nd means dependent upon ti conditions in saidlocal circuit for connecting; the local circuit to said supply circuit.

5 system of regenerative control, the combination with a supply circuitand a plurality of dynamo-electric machines severally having armaturesand field windings, of a translating device, means for connccting saidarmatures in parallel relation and said lield windings and translatingdevice in series relation therewith in an independent local circuit, andmeans directly dependent upon electrical conditions of said translatingdevice for connecting the armature and held-winding circuits in parallelrelation across said supply circuit.

l. In a system regenerative control, the combination with a supplycircuit and plurality of dynamo-electric machines severally havingarmatures and field windings, of a resistor, means for connecting saidarmatures in parallel relation and paid lield windings and resistor inseries relation therewith in an independent local circuit, and means forautoniat' :ally conuc :ting the local circuit to the supply circuit whenthe current in the local circuit attains a predetermined value.

in a syst in of regene 'ative control, the coinbinati n with a supplyci.'cuit and. a plurality of (lYllftl'llOfilGCtl'iC machines sevc allyhaving armatures and lield windings, ot' means for connecting saidarmatures in parallel relati and said lield .vindings in series relation1 rewith in independent local circuit, and relay means to automatiii theit to said supunder pr d termined local-circuit condi tions.

4. L a system of cont ol, the combination with a supply circuit, andplurality oi momentum-driven i ]121I110 9l60ill'l0 machines severallyhaving armatures and hold wind- T oil means for connecting said armaesin parallel relation and said field windin series relation therewith inan independent upon e dent local circuit, .neans d :oncitions in saidlocal circuit for automati- 7 connecting the local circuit to saidcircui with the arniatures in par- Alation, anl means acting inconjunction with said last means for subsequently automaticallyconnecting said armatures in series relation across the supply circuit.

8. In a system of control, the combination with a supply circuit, and aplurality of momentum-driven dynamo-electric inachines severally havingarmatures and field windings, of a resistor, means for connecting saidarmatures in parallel relation and said field windings and resistors inseries relation therewith in an independent local circuit, relay meansdependent upon the current traversing said resistor for automaticallyconnecting the loca circuit to said supply circuit, with the armaturesin parallel relation, and other relay means dependent upon prod terminedcircuit conditions for subsequently automatically connecting saioarmatures in series relation.

9. In a system of control, the combination with a supply circuit, and aplurality of momentum-driven dynamo-electric machines severally havingarmatures and field windings, of a resistor, a normally independentelectrical circuit comprising said armatures in parallel relation, saidlield windings and said resistor in series relation with said armatures,relay means for automatically connecting the machines to said supplycircuit under predetermined electrical conditions in the local circuitand means, including said relay means, for snosequently connecting saidin series relation across the supply circuit.

tion with a supply circuit, and a pli of momentum-driven dynamo-electricchines severally having armatures and field windings, of a resistor, anormally inc-e pendent local electrical circuit comprisiu, saidarmatures in parallel relation, i'ield windings and said resistor inseries relation with said armatures, and roll l l for automaticallyconnecting the mach to said supply circuit under pro aetermin delectrical conditions in the local circuit for automaticallyreestahlishing said local circuit under subsequent electrical conditionstherein.

11. In a system of control, the combination with a supply circuit, and amomentunroriven dynamo-electric machine having an armature and fieldwinding, 01"- means for initiall including said ma e in an independentlocal circuit, and means for automatically connecting the machine tosaid supply circuit under relatively high speed conditions and forreestahlishing said local circuit under subsequent relatively low-speedconditions.

12. In a system of control, the combination with a supply circuit, andplurality of momentum-driven dynamo-electric niachines severally havingarmatures and field windings, of means for connect' sa d armatures inparallel relation and said field windings in series relation therewithin an independent local circuit, relay means for automaticallyconnecting the local circuit to said supply circuit under predeterminedlocal-circuit conditions, and means including said relay means forsubsequently automatically connecting said armatures in series relationacross the supply circuit, said relay means being also adapted toautomatically reestablish said local circuit at the end of theregenerative period.

13. In a system of control, the combination with a plurality ofdynamo-electric machines adapt-ed for both acceleration and regenerzJlOll and severally having armatures and field windings, of acontrolling d ice for ei'lecting series-parallel control oi themachines, a reversing controlling device tor the machines, and meansassociated with said reversing device for eiiectin g dissimilar gementsof said armatures and said lield windings under predeterminedconditions. 1 in a system of control, the combination with a pluralityof dynamo-electric machines adapted for both acceleration andregeneration and severally having armatures and field windings, of acontroller for efi'ecting series-parallel control of the machines, arev" for the machines, and contact means associated with said reverserfor consaid armatures in parallel relation d field windings in seriesrelation 1 during the regenerative period. in a sy tom of regenerativecontrol, 1e combination with a supply circuit, and moment-uundrivendynamo-electric mae'le means for automatically etnic bra ring conditionsat the ener ti e period. svstem of regenerative control,

the combination with a supply circuit, and a momentunrorivcndynamo-electric machine having an armature and a normally series infield-winding circuit connected p .rallel relation thereto duringregeneration, of means for automatically effecting dy' amic brakingconditions at the end of egenerative period.

a system of regenerative control, the comoination with a supply circuitand oi momentum-driven dynamoelectric machines collectivel havin )aralle1d armatures and neld-winding cirof relay means for automaticallyetfecting dy amic braking conditions at the end of tire regenerativeperiod.

18. in a system of control, the combination with a supply circuit and adynamoelectric machine having an armature and a field winding, of meansfor connecting said armature and field winding in a local circuit underpreliminary regenerative conditions, means dependent upon conditions insaid local circuit for automatically connecting said local circuit tothe supply circult, and means for varying the field excitation underpredetermined conditions.

19. In a system or" control, the combination with a supply circuit and adynamoelectric machine having an armature and a field winding, of a rsister, means for connecting said armature, field winding ant resistorin a local c'rcuit under preliminary regenerative con linens, nieansdeoendent u v I I I A upon conditions 1 d local circuit rorautomatically connec Lg said local circuit to the supply circuit, andmeans for varying sin a substantlally consaid resistor to main" 1 cuitto supply ciic varying the field-o r tain suhstant current.

i c' nth 7 r1 machine,

i H device theieici J. c-

when in one pisition w.

supply-circuit c nne-zion when i;. another position, and means "forautoma ically i ridging th opening under predete iiiinec cnitconditions.

22. In a system of centre tion with a supply circuit,

electric machine, of a contro governing cceleration of said in a innti-po reversing device if machine, me ns associated with said rev lngdevice for conecting said niachlne 'aid controlling d vice the su plycircuit when said reversing device occu ies one position and for openinconnection when in anot ier position, and

means depend upon 0 r 'iut conditions for i automatically bridging tnepening.

sr ply-circuit c 28. in a system of control, th cornhination with asupply circuit and a dynamoelectric machine adanted for bothacceleration and regeneration, of a controlling device for governing theoperation of said machine, nrulti-position reversing device for saidmachine, inc-ans niechanically associated with said revel I device tiiorconnecting said nia :hine and said controlling device to the supplycircuit when said reversing device occupie. a position corresponding; toacceleration and for opening the supply-circuit connection when in aposition correspondinv oration, and auxiliary means d npon circuitconditions "for autoniat' dgin the opening.

In a n of control, the combination witn su ily ci-cuit, and a pluralityof dynainoelectric machines acapted for both acceleration andregencmtion and severally having arniatnres and field windings, f acontrolling device l governing the operation of said machines, annilti-position reversing device if i said machines enihodying means forconnecting said arniatures and fi ld wii din s in an independen localcircui' un in 'niinary regenerative connrenn vianicailv aSsocn ed with iiosition corresnondin to accelera- "ion and for enema, ection when 1111' clrcuit i l supoly ciron wy to con:

circuit.

tive Nntro y circuit and a nionientnni-driven d i vino-elm means forending dynainic braking conditions. estimony vhereof, I have hereunto hd my nam this 18th ray of Febru- 4 ary, 19

o inrnon TVI QLGSSQS C. C. Bummer,

cl. HITILLLLDISON.

